/* Copyright (c) 2002-2003 krzYszcz and others.
 * For information on usage and redistribution, and for a DISCLAIMER OF ALL
 * WARRANTIES, see the file, "LICENSE.txt," in this distribution.  */

#include "m_pd.h"
#include "sickle/sic.h"

#define RAMPSMOOTH_GEOMETRIC  /* geometric series (same as slide~) CHECKED */
#ifndef RAMPSMOOTH_GEOMETRIC
#define RAMPSMOOTH_LINEAR
#endif
#define RAMPSMOOTH_DEFNUP    0.
#define RAMPSMOOTH_DEFNDOWN  0.

typedef struct _rampsmooth
{
    t_sic    x_sic;
    int      x_nup;
    int      x_ndown;
    double   x_upcoef;
    double   x_downcoef;
    t_float  x_last;
#ifdef RAMPSMOOTH_LINEAR
    t_float  x_target;
    double   x_incr;
    int      x_nleft;
#endif
} t_rampsmooth;

static t_class *rampsmooth_class;

#ifdef RAMPSMOOTH_LINEAR
/* this is a true linear ramper */
static t_int *rampsmooth_perform(t_int *w)
{
    t_rampsmooth *x = (t_rampsmooth *)(w[1]);
    int nblock = (int)(w[2]);
    t_float *in = (t_float *)(w[3]);
    t_float *out = (t_float *)(w[4]);
    t_float last = x->x_last;
    t_float target = x->x_target;
    double incr = x->x_incr;
    int nleft = x->x_nleft;
    while (nblock--)
    {
    	t_float f = *in++;
	if (f != target)
	{
	    target = f;
	    if (f > last)
	    {
		if (x->x_nup > 1)
		{
		    incr = (f - last) * x->x_upcoef;
		    nleft = x->x_nup;
		    *out++ = (last += incr);
		    continue;
		}
	    }
	    else if (f < last)
	    {
		if (x->x_ndown > 1)
		{
		    incr = (f - last) * x->x_downcoef;
		    nleft = x->x_ndown;
		    *out++ = (last += incr);
		    continue;
		}
	    }
	    incr = 0.;
	    nleft = 0;
	    *out++ = last = f;
	}
	else if (nleft > 0)
	{
	    *out++ = (last += incr);
	    if (--nleft == 0)
	    {
		incr = 0.;
		last = target;
	    }
	}
	else *out++ = target;
    }
    x->x_last = last;
    x->x_target = target;
    x->x_incr = incr;
    x->x_nleft = nleft;
    return (w + 5);
}

#else

/* this ramper generates a geometric series output for a single step input */
static t_int *rampsmooth_perform(t_int *w)
{
    t_rampsmooth *x = (t_rampsmooth *)(w[1]);
    int nblock = (int)(w[2]);
    t_float *in = (t_float *)(w[3]);
    t_float *out = (t_float *)(w[4]);
    t_float last = x->x_last;
    while (nblock--)
    {
    	t_float f = *in++;
	if (f > last)
	{
	    if (x->x_nup > 1)
	    {
		*out++ = (last += (f - last) * x->x_upcoef);
		continue;
	    }
	}
	else if (f < last)
	{
	    if (x->x_ndown > 1)
	    {
		*out++ = (last += (f - last) * x->x_downcoef);
		continue;
	    }
	}
	*out++ = last = f;
    }
    x->x_last = last;
    return (w + 5);
}
#endif

static void rampsmooth_dsp(t_rampsmooth *x, t_signal **sp)
{
    dsp_add(rampsmooth_perform, 4, x, sp[0]->s_n, sp[0]->s_vec, sp[1]->s_vec);
}

static void rampsmooth_rampup(t_rampsmooth *x, t_floatarg f)
{
    int i = (int)f;
    if (i > 1)  /* CHECKME if 1 and 0 differ in any way */
    {
	x->x_nup = i;
	x->x_upcoef = 1. / (float)i;
    }
    else
    {
	x->x_nup = 0;
	x->x_upcoef = 0.;
    }
}

static void rampsmooth_rampdown(t_rampsmooth *x, t_floatarg f)
{
    int i = (int)f;
    if (i > 1)  /* CHECKME if 1 and 0 differ in any way */
    {
	x->x_ndown = i;
	x->x_downcoef = 1. / (float)i;
    }
    else
    {
	x->x_ndown = 0;
	x->x_downcoef = 0.;
    }
}

/* CHECKED */
static void rampsmooth_ramp(t_rampsmooth *x, t_floatarg f)
{
    rampsmooth_rampup(x, f);
    rampsmooth_rampdown(x, f);
}

static void *rampsmooth_new(t_symbol *s, int ac, t_atom *av)
{
    t_rampsmooth *x = (t_rampsmooth *)pd_new(rampsmooth_class);
    float f1 = RAMPSMOOTH_DEFNUP;
    float f2 = RAMPSMOOTH_DEFNDOWN;
    if (ac && av->a_type == A_FLOAT)
    {
	f1 = av->a_w.w_float;
	ac--; av++;
	if (ac && av->a_type == A_FLOAT)
	    f2 = av->a_w.w_float;
    }
    rampsmooth_rampup(x, f1);
    rampsmooth_rampdown(x, f2);
    x->x_last = 0.;
#ifdef RAMPSMOOTH_LINEAR
    x->x_target = 0.;
    x->x_incr = 0.;
    x->x_nleft = 0;
#endif
    outlet_new((t_object *)x, &s_signal);
    return (x);
}

void rampsmooth_tilde_setup(void)
{
    rampsmooth_class = class_new(gensym("rampsmooth~"),
				 (t_newmethod)rampsmooth_new, 0,
				 sizeof(t_rampsmooth), 0, A_GIMME, 0);
    sic_setup(rampsmooth_class, rampsmooth_dsp, SIC_FLOATTOSIGNAL);
    class_addmethod(rampsmooth_class, (t_method)rampsmooth_rampup,
		    gensym("rampup"), A_FLOAT, 0);
    class_addmethod(rampsmooth_class, (t_method)rampsmooth_rampdown,
		    gensym("rampdown"), A_FLOAT, 0);
    class_addmethod(rampsmooth_class, (t_method)rampsmooth_ramp,
		    gensym("ramp"), A_FLOAT, 0);
}